Frozen custard making machine



Jan. 30, 1940. c. KALTENBACH E1- Al. 2,188,551

FROZEN CUSTARD MAKING MACHINE Filed April 22. 1959 Patented Jan. `30, 1940 PATENT' OFFICE 2,188,551 FROZEN CUSTARDl MAKING MACHINE Carl Kanenbach ana Ludwig schmitt, New York, N. Y.

Application April 22, 1939, Serial No. 269,470

2 Claims.

This invention relates to frozen custard making machines.

Machines of this character are subject to rigid inspection by health authorities of different cities. For a machine to be approved, it must be inherently adapted for thorough, easy and absolutely reliable cleansing. In solving the problem, applicants perceived that the machine must have the following characteristics, which they thereupon devised in their machine.

l. The scraper blades, while mounted in a strong and reliable manner, must nevertheless be removable to facilitate the cleansing thereof.

2. The scraper blades must be removable without requiring opening up of bolts, screws or cotter pins, so as to reduce the time and labor involved, to thus avoid the tendency of the operator to shirk his duty.

3. The scraper blades should be preferably automatically ejected for removal, in order that the operator may have no option about separately cleansing the parts.

4. The mounting for the scraper blades should be such as avoid the provisions of any holes or bores which are diicult of access in cleaning.

5. The spring actuators for the scraper blades must be of such character and so mounted as to be adapted for easy cleansing and reliable inspection,

6. The rotor of the machine ought to be removable bodily from its cylinder, and desirably the scraper blades ought to drop out of the rotor as the latter is removed.

7. In a removable rotor having spring actuated removable or automatically ejected scraper blades, the mounting means for the blades must guidingly maintain the blades for movement toward and away from the rotor axis to accommodate for slight variations in the accuracy of the cylinder surface, and must include means to prevent longitudinal movement or release of the scraper blades, all arranged and coordinated for the purposes herein set forth.

It is accordingly an object of the invention to provide an improved machine for making frozen custard, which shall fulll all of the above mentioned objects, and which shall have few and simple parts for inexpensive construction and easy accessibility.

Other objects and advantages of the invention will become apparent as the specification proceeds.

With the aforesaid objects in View, the invention consists in the novel combinations and arrangements of parts hereinafter described in their preferred embodiments, pointed out in the subjoined claims, and illustrated in the annexed drawing, wherein like parts are designated by the same reference characters throughout the several views.

In the drawing:

Figure 1 is a vertical longitudinal sectional view showing a machine embodying the inve-ntion.

Fig. 2 is a horizontal sectional View taken on the line 2-2 of Fig. 1.

Fig. 3 is a View in side elevation of a blade supporting bracket.

Fig, 4 is a View of a portion of the removed rotor with a scraper blade automatically ejected therefrom.

The advantages of the invention as here outlined are best realized when all ofV its features and instrumentalities are combined in one and the same structure, but, useful devices may be produced embodying less than the whole.

It will be obvious to those skilled in the art to which the invention appertains, that the same may be incorporated in several different constructions. The accompanying drawing, therefore, is submitted merely as showing the preferred exemplication of the invention.

Referring in detail to the drawing, lI denotes a machine for making frozen custard, embodying the invention. The said machine may include end frame members I2, I3 for mounting a cylinder I4. A closure plate I5 for the front end of the cylinder may be detachably connected to the frame member I2 in any suitable manner that need not be shown. Formed in the closure plate I5 is a downwardly inclined outlet or spout that may be opened and closed by a Valve plate II pivotally mounted on the spout at I8 and operableby anintegral handle I9. In the drawingthis valve is shown in closed position. It will be obvious that any other type of valve may be used.

For feeding custard material into the cylinder, the rear end frame member I3 may carry a closure plate 20 for the cylinder, said plate 20 having a downwardly inclined passage 2| leading from a hopper 22.

Within the cylinder I4 is mounted a removable coaxial rotor 23 which agitates the custard material and scrapes frozen or partially frozen custard from the'wall of the cylinder so as to obtain a uniformly frozen custard. It will be understood that the cylinder I4 may be surrounded by any suitable refrigerating chamber, which being conventional, has not been shown herein.

Because the cylinder I4 inherently possesses some variations and cannot be formed industrially as a perfect cylinder, the rotor is provided with a plurality of scraper blades 24, each operative at a different section of the cylinder. Moreover, the scraper blades are desirably offset at equal angles to each other to facilitate the construction and particularly the mixing operation. For example, the rotor 23 is provided with four scraper blades 24, successively set apart from each other at degrees as shown.

The rotor 23 may comprise a shaft 25 removably journaled in bearings 26, 2'! of the respective cover plates l5 and 20. Said shaft may project from the bearing 21 to provide a keyed or other irregular end portion 28 for sliding coupling engagement with a motor (not shown).

For mounting the scraper blades 24, said shaft 25 may have a pair of bracket arms fixed thereon for each blade, each pair of arms being generally radial and lying along a plane parallel to the axis of the shaft. Desirably, certain intermediate brackets 29 are of angle shape, so that each provides arms 3Q at right angles to each other. Near the front end of the shaft 25 is provided a single bracket arm 3l, and at the rear end of the cylinder is provided a bracket arm 32, the latter desirably located close to the cover plate 20 so that it may have stop engagement therewith axially of the shaft, or may afford a minimum of clearance to scrape the face of the cover plate 23. Similar functions may be accomplished at the front end of the cylinder by the propeller 33 which may have four blades fixed to the shaft 25 and adapted to snugly scrape the faces of cover plate I5 and of an adjacent part of the cylinder.

Formed in the end portion of each bracket arm 30, 3l, 32 is a slot 34 that is open in an outward direction, and each slot being preferably fully open along its opposite sides. In these slots are guidingly received the thin strip or sheet metal scraper blades 24, so that each lies along a plane generally radial to the shaft 25 and parallel thereto. As shown in the drawing, the leading edge portion of each blade projects beyond its bracket arms. 'Ihe leading edge of each blade may be suitably beveled as desired for cutting into the frozen custard during scraping.

To prevent longitudinal movement and removal of the scraper blades 24, each is provided with a pin 35 near each end thereof. Each pin is arranged for stop abutment with an adjacent bracket arm of the blade, and since the pins of a blade lie between a pair of its supporting arms, the blade is thus held against removal in either longitudinal direction.

It will accordingly be seen that the scraper blades 24 are guidingly mounted in the slots 34 for movement toward and away from the shaft 25, and are removable in an outward direction from the open ended slots 34, and that the stop pins 35. will not in any Way interfere with these actions.

Also fixedly mounted on the shaft 25 are the brackets 35, each carrying at one end a suitably perforated mixing paddle 31. Each of these paddles is arranged at an angle to propel the custard mixture forward in the cylinder, and each paddle is opposite to one of the scraper blades 24. At its other end, each bracket 36 may carry a bowed strip spring 38 centrally fixedly attached thereto at 39, with the outwardly divergent arms of the spring being in the plane of a scraper blade and underlying the same so as to resiliently outwardly urge the scraper blade against `the cylinder wall.

The spring 38 is of considerable length and its range of deformation is so great as to render the spring capable of ejecting its scraper blade from its suporting bracket arms. In other words, in the operative position of the rotor, the spring is sufficiently deflected, so that upon the removal of the rotor, it is capable of moving to the ends of the bracket arms for full automatic removal of the blade.

In operation, with the cylinder at a sufficiently low temperature, custard is fed to the cylinder from the hopper 22, and with the valve il closed, the rotation of the rotor 23 is begun. The scraper blades 24 and the paddles 3l mix the custard, the paddles primarily causing the agitation and feeding the mixture forward, while the scraper blades scrape the frozen custard from the cylinder wall to assure a rapid rate of refrigeration.V

Thereafter the valve is opened periodically as desired, to obtain a quantity of the frozen custard Which flows out partly gravitationally and partly under the action of the propeller 33. The latter also imparts a nal agitation to the mix.

For cleaning, the front cover plate l5 is removed, and the rotor 23 is bodily removed from the cylinder. Now the scraper blades are removed from the bracket arms 36, 3l, 32 or drop out therefrom, or are preferably positively ejected by the springs 33. This last action is the most desirable so that it is not necessary to rely on the operator to remove the blades. Nor would removal be affected by any tendency of the blades to lock or jam or become encrusted in the bracket arms by frozen custard.

The scraper blades 24 are now easily cleansed. The slots 34 are also readily cleansed because they are open at the sides and ends. The springs 38 are readily cleansed as they are not coil springs, but rather strip springs as shown. All other parts of the rotor are also easily accessible for cleaning, and are free of any holes however minute in which bacteria might lodge. For reassembling, the blades 24 are successively replaced while the rotor is being reinserted into the cylinder.

Thus the invention fulfills the objects stated and is well adapted for practical use.

We claim:

1. In a machine for making frozen custard, a cylinder, a removable rotor therein including an axially mounted shaft, a plurality of scraper blades disposed in a longitudinal series along the cylinder wall, the successive blades being succesr" sively angularly spaced for reducing strain on the shaft, mixing paddles, hub members mounting said paddles on the shaft so that each paddle is on a side of the shaft generally opposite to an adjacent blade, pairs of arms secured to the shaft so that each pair removably carries a scraper blade, said arms being generally radially slotted, pins on each scraper blade externally laterally engaging said arms so as to prevent end wise movement of the scraper blades and to permit the scraper blades to be freely removed from said arms upon removal of the rotor from the cylinder, there being one of said hub members intermediate of the arms of each pair, and a leaf spring mounted on each hub member to provide spring fingers bearing outwardly on each scraper blade so as to eject the latter `from the slots of its arms upon removal of the rotor from the cylinder.

2. In a machine for making frozen custard, a

cylinder, a. removable rotor therein including an axially mounted shaft, a plurality of scraper blades disposed in a longitudinal series along the cylinder Wall, the successive blades being successively angular-ly spaced for reducing strain on the shaft, mixing paddles, hub members mounting said paddles on the shaft so that each paddle is on a side of the shaft generally opposite to an adjacent blade, pairs of arms secured to the shaft so that each pair removably carries a scraper blade, said blade and arms having open ended generally radial slot interengagement for movably mounting the blade, pins projecting externally of the blade and arms and mounted to prevent endwise movement of the blade without interfering With radial removal thereof, their being one of said hub members located intermediate of the arms of each pair, an arm of one blade being the arms upon removal of the rotor from the cyll0 inder.

CARL KALTEN'BACH. LUDWIG SCHMITT. 

